Biomedical subjects

Andrew D Norden

Publications and source records attributed to Andrew D Norden.

3 recordsLinked to original sources

PubMed2006

Glioma therapy in adults.

BACKGROUND: Gliomas are the most common type of primary brain tumor. Nearly two-thirds of gliomas are highly malignant lesions that account for a disproportionate share of brain tumor-related morbidity and mortality. Despite recent advances, two-year survival for glioblastoma with optimal therapy is less than 30%. Even among patients with low-grade gliomas that confer a relatively good prognosis, treatment is almost never curative. REVIEW SUMMARY: Surgery and radiation have been the mainstays of therapy for most glioma patients, but temozolomide chemotherapy has recently been proven to prolong overall survival in patients with glioblastoma. Intriguing data suggests that activity of O6-methylguanine-DNA methyltransferase (MGMT), in tumor cells may predict responsiveness to temozolomide and other alkylating agents. Novel treatment approaches, especially targeted molecular therapies against critical components of glioma signaling pathways, appear promising in preliminary studies. Optimal treatment for patients with low-grade gliomas has yet to be determined. Advances in oligodendroglioma biology have identified loss of chromosomes 1p and 19q as powerful indicators of a favorable prognosis. These same changes may predict response to chemotherapy. CONCLUSIONS: Though the prognosis for many patients with gliomas is poor, the last decade produced a number of important advances, some of which have translated directly into survival benefits. Rapid progress in the field of glioma molecular biology continues to identify therapeutic targets and provide hope for the future of this challenging disease.

Adult↗

PubMed2005

Brain metastases.

PURPOSE OF REVIEW: Brain metastases occur in 10-30% of cancer patients, and they are associated with a dismal prognosis. Radiation therapy has been the mainstay of treatment for patients without surgically treatable lesions. For patients with good prognostic factors and a single metastasis, surgical resection is recommended. The management of patients with multiple metastases, poor prognostic factors, or unresectable lesions is, however, controversial. Recently published data will be reviewed. RECENT FINDINGS: Radiation therapy has been shown to substantially reduce the risk of local recurrence after surgical resection of brain metastases, although this does not translate into improved survival. Recently, stereotactic radiosurgery has emerged as an increasingly important alternative to surgery that appears to be associated with less morbidity and similar outcomes. Other potentially promising therapies under investigation include interstitial brachytherapy, new chemotherapeutic agents that cross the blood-brain barrier, and targeted molecular agents. SUMMARY: Patients with brain metastases are now eligible for a number of treatment options that are increasingly likely to improve outcomes. Randomized, prospective trials are necessary to better define the utility of radiosurgery versus surgery in the management of patients with brain metastases. Future investigations should address quality of life and neurocognitive outcomes, in addition to traditional outcome measures such as recurrence and survival rates. The potentially substantial role for chemotherapeutics that cross the blood-brain barrier and for novel targeted molecular agents is now being elucidated.

Antineoplastic Agents↗

PubMed2004

Positive and negative network correlations in temporal lobe epilepsy.

Temporal lobe seizures are accompanied by complex behavioral phenomena including loss of consciousness, dystonic movements and neuroendocrine changes. These phenomena may arise from extended neural networks beyond the temporal lobe. To investigate this, we imaged cerebral blood flow (CBF) changes during human temporal lobe seizures with single photon emission computed tomography (SPECT) while performing continuous video/EEG monitoring. We found that temporal lobe seizures associated with loss of consciousness produced CBF increases in the temporal lobe, followed by increases in bilateral midline subcortical structures. These changes were accompanied by marked bilateral CBF decreases in the frontal and parietal association cortex. In contrast, temporal lobe seizures in which consciousness was spared were not accompanied by these widespread CBF changes. The CBF decreases in frontal and parietal association cortex were strongly correlated with increases in midline structures such as the mediodorsal thalamus. These results suggest that impaired consciousness in temporal lobe seizures may result from focal abnormal activity in temporal and subcortical networks linked to widespread impaired function of the association cortex.

Adolescent↗